Lesson 1
a push or pull on an object that can cause it to change motion
force
can cause objects to start moving, speed up, slow down stion, or change direction
force
the greater the mass of an object + the greater the pull of gravity on an object = the ___ the weight of an object
greater
energy that comes from chemical changes
(example: batteries for power, gasoline, food)
chemical energy
Energy has many forms and can ____from on form to another.
Potential energy changes to kinetic energy when the object _____.
change
moves
a force that pulls any two objects toward one another such as you toward the center of the earth
gravity
a measure of the pull (force) of the earth's gravity
weight
the ability to do work
energy
energy that comes from the flow of electricity
(example: a lamp burns because you plug it into a wall outlet)
electrical energy
An example of potential energy is a swing at the highest point on a swing set. The swing has the ____ potential energy at this point. As the swing begins to move downward, it loses its potential energy and gains kinetic energy. As the swing goes back up the kinetic energy becomes potential energy.
most
the tendency of a moving object to stay in motion ot a resting object to stay at rest
inertia
weight is dependent on _____ and _____
mass and gravity
energy that an object has because of position
(example: child at the top of slide, boulder on the edge of a cliff)
potential energy
You use _____ every time you do work or move an object.
energy
____, ______, and ____ energy are forms of energy that can affect motion.
potential, mechanical, kinetic
a force that slows or stops the motion of moving objects
friction
discovered that a moving object will continue moving in a straight line until a force causes it to slow or stop, and that an object at rest will remain at rest until a force causes it to move.
Isaac Newton
energy of motion
(example: a ball that has been kicked, swing moving downward)
kinetic energy
______ energy is stored energy but is capable of being put into motion.
potential
Chemical energy is a kind of _____ energy.
electrical
The heavier an object, the _____ the force needed to move it.
more
occurs when 2 objects rub against eachother
friction
kind of energy an object has because it can move or because it is moving
(example: a bicycle that moves when you pedal it, wind-up toys)
mechanical energy
When anything moves it has _____ energy.
mechanical
As a moving object slows down, its potential energy ____.
As the object speeds up, its potential energy ____.
increases
decreases